There exists a demand for a small, light electrochemical source of power having a high rate of discharge and a high energy storage capacity. Lithium cells each having a highly reactive lithium anode in combination with a high surface area carbon cathode and making use of one of various electrolyte materials have been developed for this market. The more popular electrolytes include thionyl chloride and sulphur dioxide having a salt such as, for example, lithium tetrachloraluminate dissolved therein.
Typical examples of prior art power sources of this type are shown in the following U. S. Pat. Nos.
4,352,867 to Catanzarite Oct. 5, 1982
4,469,763 to Walsh et al Sept. 4, 1984
4,513,067 to Kuo et al Apr. 23, 1985
4,643,958 to Thrash Feb. 17, 1987
as well as in the following published articles:
Journal of Applied Electrochemistry 11 (1981) 563-571
Journal of the Electrochemical Society March 1982, 451-457
Journal of the Electrochemical Society Vol. 134, No. 1, pages 37-40.
It has been found, however, that these battery units must be handled cautiously because of a danger of explosion. The article in the Journal of Applied Electrochemistry in its "Introduction" on page 563 states "the explosion hazard of the Li/SOCl.sub.2 cells may be related to discharge products such as elemental sulphur and/or intermediates." The article then proceeds to describe an attempt to improve such cells by the addition of BrCl to the electrolyte.
The article in the Journal of the Electrochemical society, on page 451 in the very first paragraph speaks of the "well-known explosion hazard during reversal or charging," see lines 8+. Also, refer to page 455, the first paragraph of the "Discussion," which states that"the commercialization of Li/SOCl.sub.2 high rate cells . . . is relatively limited" because of the safety factor.